Explosive priming compositions.



STATES PATENT Quinton.1

ITED. or GLASGOW, SCOTLAND.

JAQUESfOF REDDING, POLMONT ySTATION. SCIOTLAND, AND GORDON WELLS, '0F S12 ALBANS, ENGLAND, ASSIGNOBS T0 NOBELS EKPLCSIV'ES COMPANY, LIMe i EXPLOSIVE PRIMING COMPOSITION.

I Drawing.

1b all rw'ltozntmay concern:

Y Be it known that We, ARTHUR J norms and GORDON WELLS, subjects of the King ct Great Britain, residing' at Redding, Polmont Station,- Scotland and St' Album electric current b able materiahan `the pr1ming composition .fires when the current, reaching a certain.

flb'enablel the priming composition to be fired by an electric current, such fuses being Vknown as high-tension and low-tension re ,i ively. 'In the case of high-tension fuses t 'e priming composition is such that the' substance is itself ymade a conductor of the the addition of a suit strength, raises its temperature or that of some particles in it `to a point at which ignition commences andprcpagates throughout the' mass. In the case of low-tension .fuses ignition is obtained by embedding in the priming composition a fine Wire of gistinmleother material which becomes ted'by 'the' passage of the electric cur# rnt. In this case also when the temperature' of the Wire reaches a certain. Value ignition commences in the particles" at the surface of the Wire and spreads throughout the mass. When these fuses yare made up into electric detcnators for detonatingex-v plosives 'as in mines, and quarries, it is frequently necessary to fire a number ot' shots simultaneously, and for this purpose more especially in the case of loir-tension electric detonators oi' electric fuses, it is customary to connect a number of these in series and byulneans cf an exploder to pass sufficient cui-.rent to tire the whole number at once.

It is found in practice that asthe number of electric deonatcisor electric fuses connected in series increases more power is required. Two circumstances contribute tothe need for this additional power, namely (1) the extra resistance ofthe additional' fuses and (2) vthe fact that a larger current is found to be required to fire the larger` number ationce. .This necessitates a disproportionate increase in the size of the exploders as the number of shots to'be tired increases.

Specification of Letters Patent. i

Patented Aug. 4, 1914.

YApplication iled October 4, 1913. Seria No. 793,437.-

For a given type of fuse it naturally :tollc-Ws that Athe lo'we'r the temperature of ignition ot the priming composition," the less current is required to cause ignition` 4Tnis,

might be expected to hold goed for the case of a' number'of shots in series, aspivell as for single shot firing and we ind this to be the case.

he present invention relates to the manui considerablyYT reducing the temperature of ignition of the resulting mixture. Benzoyl peroxid Whenheated alone gives otf oxygen 112 'C., and this decomposition induces the explosive reaction of certain substances With- Which it may be mixed to take place almost at its c-Wn temperature of decomposition.

As examples of the" use of benzoyl peroxid in this manner We may quote the following results whic'hwere obtained .using the ordinary flash-point apparatus, with a time-interval of 10 seconds:` A

Mixture No. 1.-'A mixture oi' fulminate of mercury 60% and benzoyl peroxid 40% flashes at 112C C. Fulminate of mercury alone hashes at 180"v Cr or over.

d1' ature- No. .QT-A: cuprammonium thiosulfate (CUSQOMLLNHQ 43%, potassium chlorate 57%.

A mixture of (A) 60% and benzoyl peroxid 40% flashes at 115o C. Mixture A alone flashes instantaneously at 290o C. Below this temperature however, itl does not flash at all.

Mixture No. 3.- mixture of lead thiosulfate 4(vPbSgOQgl part, potassium chlorate 1 part, and of benzoyl peroxid (CMHOQ 1- part iiashes at 112.D C A mixture of equalparts of lead thiosulfate and potassium chlorate does not ia'sli below 200c C.

A comparison of electric detonators containing fulminate of mercury alone as priming composition, and those containing mixture No; 1 showed' that the latter required only three quartersof the current needed that the compound'known 75 wlth some violence'at a temperature of about to iire the former, While for a given ex? ploder the number of Yelectric detonators containing' mixture Nm 1 .as priming composition that could be yfired with certainty was one quarter more than the number containing fulminate alone. v

We declare that what we claimisg- 1. As a new varticlefo' manufacture, a inixture of benzoylperoxidandxan.explosive, said mixture Ihaving a. lowergteinperature of ignition or fiashingthansucli explosive.

2. As a new article of manufacture, a coinposition consisting of anfordinaiy priming composition, aboutl 60% 'to 66%,'and benzoyl pei'oxid, 40% to 33%.' 'Y

In Witness whereof, We have. hereunto signed our names' this 18th and 2d days of September 1913, in the scribing Witnesses.

ARTHUR. JAQUES. GORDON WELLS.

Witnesses tothe signature of` the said ArthurvJaques;

ALEXANDER FORBES, JAMES MITCHELL KING. f' Witnesses to the signature of theA said Gordon Wells: i A

C. LUDLow LIVINGSTON, v WILLIAM I.- DEES.

presence of two .uhY 

